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AutomationElement.GetCurrentPattern Method

Retrieves the specified pattern object on this AutomationElement.

Namespace:  System.Windows.Automation
Assembly:  UIAutomationClient (in UIAutomationClient.dll)

'Declaration
Public Function GetCurrentPattern ( _
	pattern As AutomationPattern _
) As Object

Parameters

pattern
Type: System.Windows.Automation.AutomationPattern

The identifier of the pattern to retrieve.

Return Value

Type: System.Object
The pattern object, if the specified pattern is currently supported by the AutomationElement.

ExceptionCondition
InvalidOperationException

The pattern is not supported by the element.

ElementNotAvailableException

The UI for the AutomationElement no longer exists.

GetCurrentPattern gets the specified pattern based on its availability at the time of the call.

For some forms of UI, this method will incur cross-process performance overhead. Applications can concentrate overhead by caching patterns and then retrieving them by using GetCachedPattern.

The following example shows how to use this method to retrieve a SelectionItemPattern, which is then used to select an item in a list box.

''' <summary> 
''' Sets the focus to a list and selects a string item in that list. 
''' </summary> 
''' <param name="listElement">The list element.</param> 
''' <param name="itemText">The text to select.</param> 
''' <remarks> 
''' This deselects any currently selected items. To add the item to the current selection  
''' in a multiselect list, use AddToSelection instead of Select. 
''' </remarks> 
Public Sub SelectListItem(ByVal listElement As AutomationElement, ByVal itemText As String)
    If listElement Is Nothing OrElse itemText = "" Then 
        Throw New ArgumentException("Argument cannot be null or empty.")
    End If
    listElement.SetFocus()
    Dim cond As New PropertyCondition(AutomationElement.NameProperty, itemText, PropertyConditionFlags.IgnoreCase)
    Dim elementItem As AutomationElement = listElement.FindFirst(TreeScope.Children, cond)
    If Not (elementItem Is Nothing) Then 
        Dim pattern As SelectionItemPattern
        Try
            pattern = DirectCast(elementItem.GetCurrentPattern(SelectionItemPattern.Pattern), _
                SelectionItemPattern)
        Catch ex As InvalidOperationException
            Console.WriteLine(ex.Message) ' Most likely "Pattern not supported." 
            Return 
        End Try
        pattern.Select()
    End If 

End Sub 'SelectListItem
NoteNote

For often-repeated tasks such as the one in the example, it would be more efficient to cache the pattern and use GetCachedPattern.

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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